Ngatamariki
From Pines to Brine

NZ-JAPAN GEOTHERMAL WORKSHOP

20 November 2017

OUTLINE• Outline••••The Ngatamariki Resource
Statutory Planning
Consenting
Challenges, Outcomes and Reflections

Orakonui South Spring 1

NGATAMARIKI• High temperature system in the Taupo
Volcanic Zone.
• Ngati Tahu-Ngati Whaoa Rohe• Surrounded by other high temperaturesystems

NGATAMARIKI RESOURCE> Crown exploration in mid-1980s (4 wells)
indicated large high quality resource (280oC)> Some geothermal springs along Orakanui
Stream> Area dominated by Tahorakuri plantation forest> Key pre-development reservoir parameters :> temperature 285°C> enthalpy 1230 kJ/kg (range 1180kJ/kg1280kJ/kg)> pressure 230 barg at 2500m

STATUTORY PLANNING> Resource Management Policies and Plans - Set community expectations.
> Significant influence on future consentability (easy vs hard)> Ngatamariki falls under Waikato Regional Policy Statement and Waikato Regional Plan
> Regional Plan History;> Original Waikato Regional Plan – Little guidance on management of geothermal resources> 2003 – Regional Council Proposed Variation to Regional Plan
> Draft variation classified Ngatamariki as a “Protected” geothermal system.
> Council position - no evidence there is not a flow or a connection between Ngatamariki and OrakeiKorako (a Protected System).

5 CLICK TOADDFOOTERORAKEI KORAKO• Located approx 6km north of Ngatamariki• Considered the birth place of Ngati Tahu-Ngati
Whaoa iwi
• Resource and geothermal features significant
taonga to Ngati Tahu
• Once held a third of the world’s geysers
including Minginui Geyser - once observed
erupting up to 90 metres high• Filling of Lake Ohakuri in 1961 destroyed mostof Orakei Korako Features• Four Crown wells drilled (OK1, 2, 3, and 4)

Charles Blomfield.
Orakei Korako on
the Waikato 1885.
Museum of NewZealand Te Papa
Tongarewa.

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Rainbow
Terrace 1943

Golden Fleece
Terrace 1950

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Map of Australia

KURAPAIGEYSER
Map of Africa

WAIKATO REGIONAL POLICY STATEMENT AND
WAIKATO REGIONAL PLAN
> 41 submitters> Required mediation, Council Hearings and Environment Court proceedings> Significant investment;> Technical evidence> Expert witnesses> Case supported by;> Resistivity surveys> Geochemical studies> Isotherms> Environment Court decided that, although Ngatamariki was postulated to have a hydrologicalconnection to Orakei Korako, resistivity measurements and other scientific data effectively ruled thatout.
> Final decisions on the Proposed Variation No.2 were released in June 2004.

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SUCCESS - PLANNING FRAMEWORK SUPPORTS
FUTURE DEVELOPMENTTABLE 7-1: DEVELOPMENT GEOTHERMAL SYSTEMS

13 CLICK TOADDFOOTERPROJECT DEVELOPMENT2004: ScientificInvestigations

Secured Access
Statutory Planning Processes
Scientific Investigations
Drilling and well testing

2008: Well Drillingand Testing

Conceptual model
Numerical modelConsenting
Project Development
ProcureConstruct
Commission
Handover to Operations

2009: Reservoir
ModellingPINE TREES

15 CLICK TOADDFOOTERCONSENT PROPOSAL> 60,000 t/d> 100% injection> Binary or Flash Plant> Provisions for make-up fluid> Transmission line to Rotokawa> 2 sentinel wells between Ngatamariki andOrakei Korako

Slide16

ORAKEI KORAKO
Consenting & Development Risk

> No “absolute proof” a connection doesn’texist.
> Likelihood very very low……..but not outof the question.

Ngatamariki
Power StationDestroys Birth
Place of Local Iwi

18 CLICK TOADDFOOTERCONSENT PROCESS> Consents lodged November 2009
> Main submitters;> Orakei Korako Collective> Wairakei Pastoral Ltd> DOC> Orakei Korako Collective made up of;> Tutukau East Z Trust> Tutukau Lands Company> Orakei Korako Geyserland Resort (Tourist Operator)> Orakei Korako Collective concern;> Ngatamariki development would cause adverse impacts on OK features andresource

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WAIRAKEI PASTORAL LTD CONCERNS

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DEPARTMENT OF CONSERVATION CONCERNS

21 CLICK TOADDFOOTERCONSENT DECISION> Consents granted by panel of Council appointed Commissioners following
public hearing> Key Performance Requirements;> Need to avoid pressure drawdown in the reservoir that causes;> quenching of the resource by cold water inflow or> any adverse effect on Orakei Korako> Need to avoid contamination of freshwater aquifers.

22 CLICK TOADDFOOTERORAKEI KORAKO RISK AND MITIGATION PLAN
> Objectives:> To develop appropriate Injection and Monitoring Strategies that ensure theoperation of the Ngatamariki Power Station will avoid any induced pressure ortemperature response from causing an adverse effect on the thermal surface
features at Orakei Korako.
> Bring Orakei Korako and Iwi stakeholders “into the tent”.
> Provide them with their own independent technical advisors.
> Work together on a risk mitigation plan.
> Ongoing information share through operations phase> Work through any future issues together> Turn off Ngatamariki as fall-backRISK MITIGATION PLAN
Avoid Effects on OK> Reduced first stage take of 50,000 t/d(consent provides for 60,000 t/d)
> Production from NM5, NM7 and NM11
> Deep (3500m) injection in the north (target100%)> Stand-by deep injection in the south.
> Monitor pressures at multiple
locations/depths within Ngatamariki, within
Orakei Korako and in between the twosystems> Monitor select features at Orakei Korako> Baseline Monitoring -12 months precommissioning

OKM1 & OKM2

MONITORING WELLS
OKM3S> Deep wells NMM18 and OKM1
monitoring resource depth pressures> Intermediate depth wells NMM17 andOKM2 monitoring pressure inoverlying groundwater aquifers.
> Shallow OKM3 to monitor pressurenear the springs in the tourist area

Orakei Korako

Sentinel Wells(NMM17 & 18)

ORAKEI KORAKO - MONITORING SITESFred & Maggies PoolUtility Pool

Kurapai Geyser

NMM17

CONFIDENTIAL

Orakei Korako andSentinel well pressure
trends Compared withNM2

Kurapai Geyser, Fred& Maggies Pool, Utility
Pool

28 CLICK TOADDFOOTERRESERVOIR HEALTH PROTECTED> Ngatamariki Reservoir Pressure:> Drawdown within manageable levels> Very low total pressure drawdown of only 2bar has been observed since start-up.
This is expected at 100% injection.
> This risk of cold downflow from the leak remains low as the reservoir pressure ismaintained> Sentinel Wells:> Pressure at sentinel wells showed no response to Ngatamariki development.
> Monitoring wells at Orakei-Korako> Showed no response to Ngatamariki development

29 CLICK TOADDFOOTERREFLECTIONS> Effort up-front in right areas pays dividends later> Development status – provides certainty for developers but not necessarily a slam-dunk> Inter system connectivity – you don’t know for sure until you develop one of them
> Partnerships, relationships and being transparent important

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